CHST - Construction Health and Safety Technician Health Hazards and PPE Questions and Answers

Question 1

A construction worker is tasked with dry cutting concrete block with a handheld power saw for a full 8-hour shift. According to OSHA's silica standard for construction (29 CFR 1926.1153), which of the following represents the most effective and compliant method for controlling the respirable crystalline silica hazard?

Accepted Answer

Using a saw equipped with an integrated water delivery system.

Answer

The most effective control measure listed is using a saw with an integrated water delivery system. This is an engineering control that prevents the silica dust from becoming airborne at the source. While respirators are a form of PPE, the hierarchy of controls prioritizes engineering controls over PPE. Administrative controls like restricting access or job rotation are also less effective than engineering controls.

Question 2

A safety technician calculates the required attenuation for hearing protection in an area with an A-weighted Time-Weighted Average (TWA) noise exposure of 102 dBA. The company policy is to use OSHA's standard formula for estimating workplace protection. If a worker uses earplugs with a Noise Reduction Rating (NRR) of 33, what is the estimated exposure in dBA under the protector?

Accepted Answer

76 dBA

Answer

OSHA's formula for estimating the protected A-weighted TWA from an A-weighted measurement is to subtract 7 from the NRR, and then subtract the result from the measured TWA. Calculation: NRR 33 - 7 = 26. Then, 102 dBA - 26 = 76 dBA. This estimated exposure is below the OSHA Permissible Exposure Limit (PEL) of 90 dBA and the action level of 85 dBA.

Question 3

According to OSHA regulations for personal fall arrest systems (PFAS) in construction, when must the equipment be inspected?

Accepted Answer

Before each use by the user and annually by a competent person.

Answer

OSHA 1926.502(d)(21) requires that personal fall arrest systems be inspected prior to each use for wear, damage, and other deterioration. In addition to this user inspection, the equipment must be inspected at least annually by a competent person.

Question 4

A worker is assigned to a task where the airborne concentration of a hazardous substance is 400 µg/m³. The Permissible Exposure Limit (PEL) for this substance is 50 µg/m³. The worker is provided with a half-mask air-purifying respirator. What is the minimum Assigned Protection Factor (APF) required, and does the provided respirator meet this requirement?

Accepted Answer

APF 10; Yes, the respirator is adequate.

Answer

The required APF is calculated by dividing the measured concentration by the PEL: 400 µg/m³ / 50 µg/m³ = 8. Therefore, a respirator with an APF of at least 8 is required. According to OSHA, a half-mask air-purifying respirator has an APF of 10. Since 10 is greater than the required 8, the respirator is adequate for the task.

Question 5

During lead abatement activities involving manual scraping of lead-based paint, which of the following housekeeping practices is explicitly prohibited by OSHA's Lead in Construction standard (29 CFR 1926.62)?

Accepted Answer

Using compressed air to remove lead dust from surfaces.

Answer

OSHA standard 29 CFR 1926.62(h)(5) prohibits the use of compressed air to remove lead from any surface unless it is used with a ventilation system designed to capture the dust. This practice is banned because it disperses hazardous lead dust into the air, increasing the risk of inhalation. HEPA vacuuming, wet methods, and proper disposal of contaminated clothing are all required or recommended practices.

CHST - Construction Health and Safety Technician Practice Test

CHST - Construction Health and Safety Technician Practice Test

CHST - Construction Health and Safety Technician Health Hazards and PPE Questions and Answers